docs: def watchdog_pid():
      """Get watchdog PID via ``netstat``."""
      result = sh('netstat -tulpn 2>/dev/null | grep 127.0.0.1:{:d}'
                  .format(SPHINX_AUTOBUILD_PORT), capture=True, ignore_error=True)
      pid = result.strip()
      pid = pid.split()[-1] if pid else None
      pid = pid.split('/', 1)[0] if pid and pid != '-' else None
  
      return pid